CN110915115A - Improvements in or related to a converter for interconnecting a first grid and a second grid - Google Patents
Improvements in or related to a converter for interconnecting a first grid and a second grid Download PDFInfo
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- CN110915115A CN110915115A CN201880048618.1A CN201880048618A CN110915115A CN 110915115 A CN110915115 A CN 110915115A CN 201880048618 A CN201880048618 A CN 201880048618A CN 110915115 A CN110915115 A CN 110915115A
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- 238000012423 maintenance Methods 0.000 description 2
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
- H02M7/02—Conversion of AC power input into DC power output without possibility of reversal
- H02M7/04—Conversion of AC power input into DC power output without possibility of reversal by static converters
- H02M7/12—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/145—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means
- H02M7/155—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only
- H02M7/1552—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only in a biphase or polyphase arrangement
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
- H02M7/02—Conversion of AC power input into DC power output without possibility of reversal
- H02M7/04—Conversion of AC power input into DC power output without possibility of reversal by static converters
- H02M7/12—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/145—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means
- H02M7/155—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only
- H02M7/162—Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only in a bridge configuration
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
- H02M7/42—Conversion of DC power input into AC power output without possibility of reversal
- H02M7/44—Conversion of DC power input into AC power output without possibility of reversal by static converters
- H02M7/48—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/4835—Converters with outputs that each can have more than two voltages levels comprising two or more cells, each including a switchable capacitor, the capacitors having a nominal charge voltage which corresponds to a given fraction of the input voltage, and the capacitors being selectively connected in series to determine the instantaneous output voltage
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Abstract
一种转换器组件（10；60）包括用于互连第一电网和第二电网（14，18）的转换器（12；62）。转换器（12；62）包括至少一个控制模块（22），其被编程以便根据存储在其中的控制程序而直接控制转换器（12；62）的开关模块（26）中的一个或多个开关（24）的开关。转换器（12；62）还包括至少一个能量存储装置（28），其被配置成存储能量以便至少部分地向至少一个对应控制模块（22）供应功率。转换器组件（10；60）另外包括高电平控制器（48），其被布置成与转换器（12；62）和在其中的所述或每个控制模块（22）通信。高电平控制器（48）被编程以便将转换器（12；62）从在线状态转变到离线状态，在所述转变期间，转换器（12；62）内的所述或每个能量存储装置（28）释放存储在其中的能量。高电平控制器（48）被进一步编程以便在从在线状态到离线状态的所述转变期间替换所述转换器（12；62）的至少一个控制模块（22）的控制程序。
A converter assembly (10; 60) includes a converter (12; 62) for interconnecting a first grid and a second grid (14, 18). The converter (12; 62) includes at least one control module (22) programmed to directly control one or more switches in the switch module (26) of the converter (12; 62) according to a control program stored therein (24) switch. The converter (12; 62) also includes at least one energy storage device (28) configured to store energy for supplying power, at least in part, to at least one corresponding control module (22). The converter assembly (10; 60) additionally comprises a high level controller (48) arranged to communicate with the converter (12; 62) and the or each control module (22) therein. The high level controller (48) is programmed to transition the converter (12; 62) from an online state to an offline state, during which transition the or each energy storage device within the converter (12; 62) (28) Release the energy stored in it. The high level controller (48) is further programmed to replace the control program of at least one control module (22) of the converter (12; 62) during said transition from the online state to the offline state.
Description
Technical Field
The invention relates to a converter assembly.
Background
In power transmission networks, Alternating Current (AC) power is typically converted to Direct Current (DC) power for transmission via overhead lines and/or subsea cables. This conversion eliminates the need to compensate for AC capacitive loading effects imposed by the transmission line or cable and reduces the cost of the line and/or cable per kilometer and thus becomes cost effective when power needs to be transmitted over long distances.
The converter is used to convert AC power to DC power. Switches, such as semiconductor switching elements, are key components of such converters and are used to help convert AC power to DC power and vice versa. Typically, the switches are controlled by one or more control modules, and in some cases it would be useful to be able to replace the control program according to which a particular control module is controlling the switches of one or more associated switches.
For example, a control program replacing a control module within a converter that has been brought into service may be used to take advantage of improved control and protection algorithms for switches that may have been developed with a posteriori knowledge of operational experience (hindsight). Also, if a defect is detected in an existing control program, the control program may be replaced to mitigate the risk of an associated converter failure.
Disclosure of Invention
According to a first aspect of the present invention, there is provided a converter assembly comprising:
a converter for interconnecting a first electrical grid and a second electrical grid, the converter comprising:
at least one control module programmed to directly control switching of one or more switches in a switching module of the converter in accordance with a control program stored therein; and
at least one energy storage device configured to store energy to at least partially supply power to at least one corresponding control module; and
a high-level controller arranged in communication with the converter and the or each control module therein, the high-level controller being programmed to transition the converter from an online state to an offline state, during which transition the or each energy storage device within the converter releases energy stored therein, and further being programmed to replace the control program of at least one control module of the converter during the transition from an online state to an offline state.
Replacing the control program of one or more control modules (i.e. updating the control program) during the transition of the converter from the online state to the offline state means that the control and protection functions provided by the or each control module are not required temporarily and therefore there is no requirement for one or more duplicate control modules and conversion arrangements which would otherwise be necessary to maintain the above-described control and protection functions.
Furthermore, during such a transition, the switching of the or each switch within the converter has stopped and thus the main source of electromagnetic interference is removed. The absence of electromagnetic interference means that it is unlikely that the replaced control program has become corrupted, and therefore there is a substantial reduction in the likelihood of a failure of the process of replacing the control program of one or more control modules.
However, because the or each energy storage device has not yet been fully released, the power supply is retained to permit the or each control module to continue operating in a manner that allows its control program to be replaced.
Furthermore, the control procedure of replacing one or more such control modules in the aforementioned manner takes place without requiring access to the converter, for example by a maintenance engineer, and therefore without requiring a grounding down process or the like.
Preferably, the converter comprises a plurality of switch modules, each of said switch modules comprising a plurality of switches connected in parallel with a respective corresponding energy storage device, and each of said switch modules being arranged to communicate directly with a respective corresponding control module programmed to control directly the switches of a plurality of said switches.
This arrangement brings the benefits of the present invention to a particular class of converters that utilize a stepped variable voltage source to generate voltage waveforms that permit them to provide the above-described power transfer functionality between an AC network and a DC network.
Optionally, the converter comprises a switch module comprising a plurality of switches, each of said switches having an energy storage device connected in parallel therewith and each of said switches being arranged to communicate directly with a respective corresponding control module programmed to control the switch of said corresponding switch directly.
This arrangement brings the benefits of the present invention to another class of converters that rely on the line voltage of the AC network to effect commutation of the switches therein.
The converter may include a plurality of control modules and the high level controller may be programmed to replace the control programs of a subset of all the control modules.
Having the high level controller so programmed allows the replacement control program to be tested without the risk of unduly adversely affecting the normal operation of the converter.
In a preferred embodiment of the invention, the converter comprises a plurality of control modules and the high level controller is programmed to replace the control programs of all the control modules simultaneously.
For example, replacing the control programs of all control modules simultaneously significantly reduces the time required to replace the control programs of all control modules, and thus the cost of performing such updates, as compared to doing so serially (i.e., one after another), since converter downtime is greatly reduced.
Furthermore, minimal manpower is required since replacement of the control program can be initiated and performed by a single maintenance engineer via operation of the high level controller.
Furthermore, the security of the update is improved, since the replacement of the control program is controlled on the basis of a single source, i.e. a single replacement control program propagated by the high-level controller, instead of a plurality of separate copies of the replacement control program.
Preferably, the or each control module is configured to check the replacement control program received from the high-level controller and to communicate the result of the check of the received replacement control program to the high-level controller.
The inclusion of one or more such control modules permits detection of corrupt code in the communicated replacement control program.
In another preferred embodiment of the invention, the high level controller is programmed to re-send the replacement control program to a given control module upon receiving a check message indicating an error in the replacement control program received by the control module.
The inclusion of such a high level controller helps to ensure that replacement of the control program of a given control module continues, but in a manner that maintains the integrity of the given control module.
The high level controller may be programmed to abort further attempts to replace the control program of a given control module after receiving a plurality of check messages indicating errors in the replacement control program received by the given control module.
A high level controller programmed in this manner helps to ensure that sufficient time remains in the transition of the converter from its on-line state to its off-line state so that replacement of the control program of one or more other control modules can still occur.
Optionally, the high level controller additionally establishes a minimum required energy storage level for the or each energy storage device, the or each respective minimum required energy storage level corresponding to a remaining amount of energy release time.
Having the high level controller establish such a minimum required energy storage level for the or each energy storage device helps to ensure that the associated control module has sufficient time for its control program to be replaced before the available power is drained to the extent that operation of such control module is no longer possible.
Preferably, after checking the or each alternative control program by the or each control module, the high level controller checks the energy storage level of the or each energy storage device against the corresponding established minimum required energy storage level.
Having such a high level controller provides the option of, for example, discontinuing replacement of the control program of the or each control module associated with the energy storage device with an energy level below the corresponding established minimum required energy storage level.
In yet another preferred embodiment of the invention, the high level controller programmed to switch the converter from the on-line state to the off-line state comprises switching the converter to the standby mode before the or each energy storage device within the converter begins to release energy stored therein.
Having a high-level controller so programmed allows the converter to be in a state, i.e. in its standby mode, in which the main source of electromagnetic interference is reduced as the current is greatly reduced, so that it is therefore possible to safely pass control program data to the or each control module in preparation for replacement of the control program thereon without having to discharge the or each energy storage device which has not yet been activated. As a result, the remaining time available for completing the replacement of the or each control procedure (i.e. as provided by the release time of the or each energy storage device) is maximised.
Drawings
The following is a brief description of a preferred embodiment of the invention, by way of non-limiting example, with reference to the following drawings, in which:
fig. 1 shows a part of a converter assembly according to a first embodiment of the invention;
FIG. 2(a) shows a schematic diagram of a switch module within a first converter of the converter assembly shown in FIG. 1;
FIG. 2(b) shows a schematic diagram of an alternative switch module;
FIG. 3 shows a schematic diagram of a second transducer assembly, wherein the first transducer, partially shown in the transducer assembly shown in FIG. 1, is replaced by a second transducer;
fig. 4 shows a schematic diagram of a part of a switch module within the second converter shown in fig. 3.
Detailed Description
A converter assembly according to a first embodiment of the present invention is generally indicated by reference numeral 10 and is shown in fig. 1.
The first converter assembly 10 includes a converter 12 (only a portion of which is shown in fig. 1) which, in use, interconnects a first electrical grid 14, which in the illustrated embodiment is a three-phase A, B, C AC network 16, with a second electrical grid 18, which in the illustrated embodiment is a DC network 20. In other embodiments of the invention (not shown), the properties of the first and second electrical networks 14, 18 may differ from those of the first embodiment.
The converter 12 includes a plurality of control modules 22, each of the plurality of control modules 22 being programmed to directly control the switching of a plurality of switches 24 in a corresponding switch module 26 of the converter 12 in accordance with a control program stored therein. The converter 12 further comprises a plurality of energy storage devices 28, each of said plurality of energy storage devices 28 being configured to store energy for supplying power at least partially to a corresponding control module 22, i.e. each energy storage device 28 is configured such that it is capable of transferring some of its stored energy in a manner that enables it to supply power to an associated control module 22, although its primary purpose may not be to supply power to said associated control module 22.
More particularly, the converter 12 includes hundreds of switch modules 26 in each leg portion (only one of such leg portions, i.e., the lower leg portion 30B, is shown in FIG. 1). By way of a specific example, the number of switch modules 26 may be 352, although this may vary from one converter to another, depending, for example, on the exact nature and performance ratings of the components included in each switch module 26, the parameters of the first and second electrical networks 14, 18, and the desired ratings of the overall power transmission scheme.
The lower leg portion 30B shown forms part of a converter limb that corresponds to phase a of the three-phase AC network 16, and includes an upper leg portion (not shown) that extends on the other side of the AC terminal 32A within the converter limb. The converter 12 further comprises two further converter branches (not shown), each of which corresponds to a respective further phase B, C of the three-phase AC network 16 and each of which comprises an upper branch portion and a lower branch portion, which in turn comprises hundreds of switching modules 26.
It follows that a typical converter 12 will comprise hundreds of switch modules 26 in its respective converter branches, for example more than 2100 in the illustrated embodiment.
In the embodiment shown in fig. 1, the switch modules 26 are connected in series with each other, and each switch module 26 has a plurality of switches 24 connected in parallel with an energy storage device 28 in the form of a capacitor 36. Each switch 24 comprises a semiconductor device 38 in the form of, for example, an Insulated Gate Bipolar Transistor (IGBT), which is connected in parallel with an anti-parallel diode 40. However, it is possible to use another form of energy storage device, as well as other semiconductor devices and other switching devices.
Fig. 2(a) shows by way of example a first type of switch module 34 included in each limb portion 30B of the converter 12 shown in fig. 1.
The first type of switch module 34 includes first and second pairs 42, 44 of switches 24 and capacitors 36 connected in a known full-bridge arrangement to define a 4-quadrant bipolar module. During operation of converter 12, i.e., when converter 12 is in an online state, the switching of switch 24 selectively directs current through capacitor 36 or causes current to bypass capacitor 36 so that first sub-module 24 may provide a zero, positive or negative voltage and may conduct current in both directions.
Fig. 2(b) illustrates an example alternative second type of switch module 46 that may be included in one or more leg portions of the converter 12 shown in fig. 1, either in place of or in addition to the first type of switch module 34 described above. The second type of switch module 46 includes only the first pair 42 of switches 24 connected in parallel with the capacitor 36 in a known half-bridge arrangement to define a 2-quadrant unipolar module. In a similar manner to the first type of switch module 34, during operation of the associated converter, the switches of the switches 24 in the second type of switch module 46 again selectively direct current through the capacitor 36 or cause current to bypass the capacitor 36 so that the second type of switch module 46 can provide zero or positive voltage and can conduct current in both directions.
In this way, in the illustrated embodiment, it is possible to establish a combined voltage within each branch portion 30B by combining the individual voltages available from each switch module 26 (i.e., from each switch module 34 of the first type). Thus, each of the switch modules 26 work together to permit each branch portion 30B to provide a stepped variable voltage source, which allows a stepped approximation to be used by each branch portion 30B to generate a voltage waveform.
Operation of switch modules 26 in each limb portion 30B of converter 12 in this manner may be used to generate AC voltage waveforms corresponding to each phase A, B, C of AC network 16 at AC terminals 32A (only one shown in fig. 1), and thereby enable converter 12 to transfer power between AC network 16 and DC network 20.
Each switch module 26 is arranged to communicate directly with a respective corresponding control module 22, which respective corresponding control module 22 is programmed to directly control the switching of the switches 24 therein. In other embodiments of the invention (not shown), two or more switch modules may be arranged in direct communication with the same single control module 22, the single control module 22 being programmed to directly control the switching of the switches 24 among all the switch modules 26, the single control module 22 being so arranged as to be in direct communication with the switch modules 26.
At the same time, the capacitor 36 within each switch module 26 is used to supply power to the corresponding control module 22, the respective switch module 26 being arranged to communicate directly with the corresponding control module 22. In embodiments where multiple switch modules 26 share a common control module 22, two or more respective capacitors 36 within each such switch module 26 may act together, or a single capacitor 36 may act individually to supply power to the shared common control module 22.
It follows that the converter 12 shown comprises the same number of control modules 22 as the number of switch modules 26, i.e. by way of example over 2100 in the embodiment described.
Continuing with the converter assembly 10 as a whole as shown in fig. 1, the assembly 10 further includes a high level controller 48 arranged to communicate with the converter 12 through each of the control modules 22 included within the converter 12. High-level controller 48 oversees the overall operation of converter 12, such as establishing the individual current and voltage requirements that each leg portion 30B must provide, while the corresponding control module 22 directly controls the individual switches within converter 12 (whose coordinated switches are needed to cause converter 12 to provide the established current and voltage requirements).
Communication between the high-level controller 48 and each of the control modules 22 is via a passive optical network 50 that includes an optical coupler 52, the optical coupler 52 serving to interface between the high-level controller 48 and each of the control modules 22. In other embodiments of the present invention (not shown), the communication between the high-level controller 48 and each of the control modules 22 may be a separate (i.e., non-networked point-to-point) optical fiber running between the high-level controller 48 and each of the control modules 22.
In yet another embodiment of the present invention, other communication techniques may be employed.
During such a transition of the converter 12 from the online state to the offline state, each energy storage device 28, i.e., each capacitor 36 in each switch module 26, discharges energy stored therein. With respect to the converter assembly 10 shown and described above, this release of stored energy of each capacitor 36 is initiated by having the high level controller 48 block the converter 12, i.e., instruct each control module 22 to open each switch 24 being controlled, and then open the circuit breaker 54 associated with each phase A, B, C of the AC network 16.
In addition to the above, the high level controller 48 is further programmed to replace the control program of each control module 22 within the converter 12 during the aforementioned transition of the converter 12 from the online state to the offline state, and more particularly, to replace the control program of each control module 22 as each capacitor 36 discharges the energy stored therein. More particularly, high-level shifter 12 is still programmed so as to replace the control programs of all control modules 22 at the same time.
Alternatively, the high level controller 48 may be programmed to transition the converter 12 to the standby mode before each capacitor 36 begins to discharge the energy stored therein, i.e., before the converter 12 is blocked and the circuit breaker 54 is opened.
In this standby mode, the operation of the converter 12 is slowed down (dead back), wherein the power and current levels are reduced, and the frequency at which the switches 24 within the switch modules 26 are switched is reduced to a minimum level to simply maintain the charge in the associated capacitors 36.
Thereafter, the high level controller 48 may be programmed to communicate control program data to one or more control modules 22, for example, for temporary storage in each such control module 22 in preparation for replacement of the control program of each such control module 22. Thus, such a step provides a maximum amount of time for a replacement to be subsequently performed.
In any event, the high-level controller 48 replaces the control program of a given control module 22 by communicating the replacement control program to the control module 22 via the passive optical network 50.
At this point, because no capacitor 36 has been fully discharged, the stored energy remains within each capacitor 36, and thus each capacitor can continue to supply power to each associated control module 22 in order to permit each control module 22 to receive an alternate control program from high-level controller 48, i.e., a programming interface (not shown) within each control module 22 may be powered to permit reprogramming of control module 22.
At the same time, each control module 22 is configured to check (again powered by the residual energy in the associated capacitor 36) for errors in the replacement control program received from the high-level controller 48, and thereafter to pass the check results of the received replacement control program to the high-level controller 48, for example by means of a check message sent to the high-level controller 48. One way in which each control module 22 may perform such checks is to store replacement control programs in non-volatile memory blocks within the control module 22 and perform a cyclic redundancy check on the stored files. A benefit of storing the replacement control program in the non-volatile memory block is that reprogramming of the control module 22 can be suspended prior to its startup, for example if sufficient time does not remain to completely replace the original control program, and the replacement control program remains temporarily in the non-volatile memory block, for example when the converter 12 is powered up again. Thereafter, reprogramming of (instigate) control module 22 may again be instigated during a subsequent transition of converter 12 from the online state to the offline state. However, other ways of performing the check are also possible.
The high level controller 48, upon receiving a check message indicating an error in the replacement control program received by a given control module 22, is programmed to re-send the replacement control program to that control module 22. This retransmission of the replacement control program can take place by a general broadcast to all control modules 22, wherein only those control modules 22 which have previously identified an error contribute to the broadcast.
The high level controller 48 is further programmed to abort further attempts to replace the control program of a given control module 22 after receiving a plurality of check messages indicating errors in the replacement control program received by the given control module 22. Further, if the number of control modules 22 that send check messages indicating errors is excessive, e.g., more than about 1% of the total number of control modules 22, the high level controller 48 may consider aborting the process of replacing the control programs of all control modules 22.
As described above, the high level controller 48 additionally establishes a minimum required energy storage level for each energy storage device 28 (i.e., each capacitor 36). Each respective minimum required energy storage level corresponds to a remaining amount of energy release time, i.e., a remaining length of time (at a given expected discharge rate) for which the respective capacitor 36 will be able to provide sufficient energy to power the control module 22 with which it is operatively associated.
In one example, the minimum energy storage level of each capacitor 36 may be utilized in such a manner that, after the examination of the or each replacement control program by each control module 22 indicates successful delivery of the replacement control program, the high level controller 48 examines the energy storage level of each capacitor 36, i.e., the actual amount of energy remaining in each capacitor 36, against the corresponding established minimum required energy storage level. The high level controller 48 does so to determine whether each capacitor 36 has sufficient remaining energy at that stage to allow sufficient time, i.e., whether each capacitor 36 will be able to continue to power the associated control module 22 for a sufficient period of time, to permit the control program of the control module 22 to be replaced.
When the replacement of the control program for each control module 22 is completed, each associated switch module 26 becomes operable under the control of the new replacement control program, and the respective control module 22 reestablishes normal communication with the high level controller 48 before the remaining stored energy is depleted and the associated switch module 26 is powered down.
Any control modules 22 and associated switch modules 26 that fail to re-establish normal communication with the high level controller 48 (which may indicate a failure of the replacement control procedure) may be logged and their status investigated before the converter 12 is re-powered as part of a transition back to the online state.
If the control procedure replacing a given control module 22 and associated switch module 26 is not successfully completed, a switch module protection element (not shown), such as an electromechanical bypass switch, may be operated to bypass the particular switch module 26 from the remaining switch modules 26 in a given limb portion 30B, i.e., to effectively remove the particular switch module 26 from the current path through the given limb portion 30B to allow the limb portion 30B to continue operating without the particular switch module 26. In some embodiments of the invention, it may be necessary for each control module 22 to: upon causing the control program of each of the control modules 22 to be replaced, failsafe operation of the respective electromechanical bypass switch (which remains operable when the control program of the control module 22 is replaced) is prevented by, for example, sending appropriate control signals from a programming interface therein.
A schematic diagram of a second converter assembly 60 is shown in fig. 3. The second converter assembly 60 is very similar to the first converter assembly 10 and similar features share the same reference numerals. However, in the second converter assembly 60, the first converter 12 is replaced by a second converter 62.
The second converter 62 again interconnects the first electrical grid 14 and the second electrical grid 18, i.e. the three-phase A, B, the C AC network 16 and the DC network 20, and the second converter 62 further comprises a plurality of switch modules 26. However, the switch modules 26 in the second converter 62 are arranged in a different manner than those in the first converter 12.
More particularly, the second converter 62 includes six switch modules 26, each switch module 26 corresponding to a limb portion 30A, 30B of a given converter limb 64A, 64B, 64C within the second converter 62, and each of the switch modules 26 being made up of a string of serially connected switches 24. However, in this embodiment, each of the switches 24 is a semiconductor device 38 in the form of a thyristor 66. In yet another embodiment of the present invention, another different semiconductor device 38 may be used, such as a diode, a Light Triggered Thyristor (LTT), a gate turn-off thyristor (GTO), a Gate Commutated Thyristor (GCT), or an Integrated Gate Commutated Thyristor (IGCT).
Each thyristor 66 has a respective individual control module 22 with which the respective individual control module 22 is arranged to communicate directly, wherein each such control module 22 is programmed to directly control the switching of the respective thyristor 66 in accordance with a control program stored within said control module 22. In other embodiments of the present invention, two or more switches 24, i.e., two or more thyristors 66, may be arranged to communicate directly with a single shared control module 22.
In any case, typically, each switch module 26 will comprise a string of series-connected switches having tens of thyristors 66 therein, for example 10 to 100, and thus the second converter 62 similarly comprises a correspondingly large number of control modules 22.
Each thyristor 66 has an energy storage device 28 connected in parallel therewith in the form of a snubber capacitor 68 within a resistor-capacitor snubber circuit 70, the energy storage device 28 being electrically connected to the anode of each respective thyristor 66, as shown schematically in fig. 4. While the primary purpose of each such snubber capacitor 68 is to suppress rapid rises in voltage across the respective thyristor 66, some of its stored energy may be scavenged, for example, by an electrolytic storage capacitor within the power supply circuit 72 to power the corresponding control module 22.
The second converter 62 and the switch module 26 therein are similarly arranged to communicate with the high level controller 48 via point-to-point optical fibers 74, although other communication techniques are possible. Thus, the high level controller 48 in the second converter assembly 60 is programmed in substantially the same manner as the high level controller 48 in the first converter assembly 10, i.e. the transition of the second converter 62 from an online state (in which the associated circuit breaker (not shown) is closed and the second converter is unblocked with the thyristor 66 switch therein) to an offline state (in which the second converter 62 is blocked by preventing the thyristor 66 from switching and the associated circuit breaker is open) and the control program of each control module 22 is replaced simultaneously during the aforementioned transition.
Claims (11)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP17174297.6A EP3410590A1 (en) | 2017-06-02 | 2017-06-02 | Improvements in or relating to converters for interconnecting first and second electrical networks |
| EP17174297.6 | 2017-06-02 | ||
| PCT/EP2018/063493 WO2018219735A1 (en) | 2017-06-02 | 2018-05-23 | Improvements in or relating to converters for interconnecting first and second electrical networks |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110915115A true CN110915115A (en) | 2020-03-24 |
Family
ID=58992766
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201880048618.1A Pending CN110915115A (en) | 2017-06-02 | 2018-05-23 | Improvements in or related to a converter for interconnecting a first grid and a second grid |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US20200144931A1 (en) |
| EP (1) | EP3410590A1 (en) |
| CN (1) | CN110915115A (en) |
| WO (1) | WO2018219735A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102238380B1 (en) * | 2019-02-08 | 2021-04-08 | 효성중공업 주식회사 | Sub-module for dc-dc converting and update method of sub-module program |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101345483A (en) * | 2008-05-27 | 2009-01-14 | 北京先行电气有限公司 | Rail traction AC cophase supply apparatus based on three-phase series voltage source type symmetry transformation |
| WO2011124260A1 (en) * | 2010-04-08 | 2011-10-13 | Areva T&D Uk Limited | Modularised converter for hvdc and statcom |
| EP2595302A1 (en) * | 2011-11-21 | 2013-05-22 | ABB Technology AG | Method and device for servicing individual power module during operation of a modular multicell converter |
| CN104584406A (en) * | 2012-09-04 | 2015-04-29 | Abb技术有限公司 | Switching DC-DC Converter |
| EP2937986A1 (en) * | 2014-04-25 | 2015-10-28 | Alstom Technology Ltd | A control module |
| US20160079879A1 (en) * | 2014-09-15 | 2016-03-17 | Abb Technology Ag | Method For Controlling Of A Modular Converter |
-
2017
- 2017-06-02 EP EP17174297.6A patent/EP3410590A1/en not_active Ceased
-
2018
- 2018-05-23 CN CN201880048618.1A patent/CN110915115A/en active Pending
- 2018-05-23 WO PCT/EP2018/063493 patent/WO2018219735A1/en active Application Filing
- 2018-05-23 US US16/617,252 patent/US20200144931A1/en not_active Abandoned
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101345483A (en) * | 2008-05-27 | 2009-01-14 | 北京先行电气有限公司 | Rail traction AC cophase supply apparatus based on three-phase series voltage source type symmetry transformation |
| WO2011124260A1 (en) * | 2010-04-08 | 2011-10-13 | Areva T&D Uk Limited | Modularised converter for hvdc and statcom |
| EP2595302A1 (en) * | 2011-11-21 | 2013-05-22 | ABB Technology AG | Method and device for servicing individual power module during operation of a modular multicell converter |
| CN104584406A (en) * | 2012-09-04 | 2015-04-29 | Abb技术有限公司 | Switching DC-DC Converter |
| EP2937986A1 (en) * | 2014-04-25 | 2015-10-28 | Alstom Technology Ltd | A control module |
| US20160079879A1 (en) * | 2014-09-15 | 2016-03-17 | Abb Technology Ag | Method For Controlling Of A Modular Converter |
Also Published As
| Publication number | Publication date |
|---|---|
| US20200144931A1 (en) | 2020-05-07 |
| WO2018219735A1 (en) | 2018-12-06 |
| EP3410590A1 (en) | 2018-12-05 |
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